Toffee is a caramelised sugar confection and a featured ingredient in many candy bars and desserts. It's also the delicious crispy coating on toffee apples, a popular treat at fairs and outdoor events. You can make your own toffee syrup at home with a can of sweetened condensed milk. The process is about as simple as it gets -- you don't even have to open the can! -- and the results will add a extra dose of deliciousness to your favourite desserts.
Peel the label from the can of milk.
Place the can, unopened, in the pot. Fill pot with enough water to submerge can completely.
Bring the water to a slow, steady boil. Boil for 3 to 4 hours. Check occasionally to make sure the can is always fully submerged, as the can could explode if it boils dry and becomes overheated. Add more water if necessary.
Remove water from the heat. Use tongs to remove the can from the pot and place on the wire rack or other heat-safe surface. Let the can cool.
Open the can when you are ready to use the toffee. The unopened can of toffee should keep for at least several weeks.
Check to make sure the milk is pre-sweetened. Do not use evaporated milk. Sweetening the toffee yourself is messy and an unnecessary hassle. Since some recipes call for a 3-hour boil and others call for a 4-hour boil, you may want to test both cooking times. If a 3-hour boil leaves the toffee too syrupy, try another can at 4 hours and use the syrupy toffee to pour on ice cream, cake or fruit.
Take precautions to not let the water in the pot boil down so that the can is no longer submerged. A dry, overheated, unopened can has the potential to explode. While some sources say your toffee will keep "indefinitely" if the can is unopened, make sure to check for signs of spoilage when you use it. If your toffee smells or tastes even mildly spoiled, discard.